Idea 1: 1. Fill the 12 liter jug completely.
2. Pour the contents of the 12 liter jug into the 6 liter jug. This will leave you with 6 liters in the 12 liter jug.
3. Empty the 6 liter jug.
4. Pour the remaining 6 liters from the 12 liter jug into the now empty 6 liter jug.
5. You now have 6 liters in the 6 liter jug.

Idea 2: 1. Fill the 12 liter jug completely.
2. Pour the contents of the 12 liter jug into the 6 liter jug. This will leave you with 6 liters in the 12 liter jug.
3. Empty the 6 liter jug.
4. Pour the remaining 6 liters from the 12 liter jug into the now empty 6 liter jug.
5. You now have 6 liters in the 6 liter jug.

Improved Answer:
1. Fill the 12 liter jug completely.
2. Pour the contents of the 12 liter jug into the 6 liter jug until the 6 liter jug is full. This will leave you with 6 liters in the 12 liter jug and the 6 liter jug completely filled.
3. Empty the 6 liter jug.
4. Pour the remaining 6 liters from the 12 liter jug into the now empty 6 liter jug.
5. You now have 6 liters in the 6 liter jug.

Full Answer:
To measure 6 liters using a 12 liter jug and a 6 liter jug, follow these steps:
1. Fill the 12 liter jug completely.
2. Pour the contents of the 12 liter jug into the 6 liter jug until the 6 liter jug is full. This will leave you with 6 liters in the 12 liter jug and the 6 liter jug completely filled.
3. Empty the 6 liter jug.
4. Pour the remaining 6 liters from the 12 liter jug into the now empty 6 liter jug.
5. You now have 6 liters in the 6 liter jug.